DESCRIPTION: (adapted from the application): Viral diseases are a major threat to the pediatric and the adult populations. The rapid emergence and spread of relatively new human pathogens such as HIV, the increasing morbidity and mortality associates with persistent infection with agents such as Hepatitis C as well as the episodic and often unexplained reemergence of pathogens such as Ebola virus underscore the need for well trained investigators who can respond rapidly to such public health problems. The goal of this research training grant is to prepare physicians (M.D. and M.D./Ph.D.) for careers as independent investigators specifically in the area of viral pathogenesis, with a primary focus on virus/host interactions. The twelve faculty members representing the key training personnel for this program have been selected for their strong track record in the area of virus- host interaction, their ability to bridge clinical and basic arenas, and their genuine commitment to training future physician-scientists. The recent recruitment and promotion of several of thee individuals at Mt. Sinai underscores the institutional commitment to developing strong and complementary research programs, not only within the basic science departments but also within the clinical departments. Each of the investigators plays a major role in the graduate school as well as in his or her respective clinical department and has developed extensive collaborative interactions that will provide the trainees a critical and accessible network of expertise. The program is designed to expand the training in the recently reorganized Adult and Pediatric Infectious Diseases fellowships. These programs and their department have undergone recent changes in leadership, with the appointment of the Co-Directors as Division Heads and a major emphasis on training future physician-scientists. The candidates will enter a research training track in their second year of fellowship and will be candidates for training grant funding for their third (PGY6) and fourth (PGY7) year. The major activity during the third and fourth year of the fellowship will be mentored laboratory investigation on an individual project. This experience will be complemented by participation in the core course of the multidisciplinary Ph.D. program Molecular Basis of Diseases , weekly journal club, weekly laboratory data sessions and divisional, departmental and institutional research conferences. The goal of this program is to provide the trainees with the necessary skills and training to effectively compete for grant awards as the next step in their transition to independent careers as infectious diseases physician-scientists.